@article{MAKHILLJAVA20054111450,
    title = {Isolation and Characterization of Infectious Bronchitis Virus Strain 4/91 from Commercial Layer Chickens in the Sudan},
    journal = {Journal of Animal and Veterinary Advances},
    volume = {4},
    number = {11},
    pages = {910-912},
    year = {2005},
    issn = {1680-5593},
    doi = {javaa.2005.910.912},
    url = {https://makhillpublications.co/view-article.php?issn=1680-5593&doi=javaa.2005.910.912},
    author = {A. Ballal,A.E. Karrar and},
    keywords = {Avian,infectious,bronchitis,strain,4/91},
    abstract = {Outbreaks of suspected IB disease occurring in a number of commercial layer flocks at Khartoum and El Gazira states were studied during years (2000- 2001). Affected birds were of different breeds (Lohmann, Bovans Hisex). Their ages were from 5 / –7 months. The main clinical signs varied from mild respiratory signs to diarrhea sometimes yellowish in colour. Drop in egg production (up to 60%) was recorded in some flocks. IB virus was isolated from these outbreaks. Using virus neutralization (VN) and haemagglutination inhibition (HI) tests, three of these IB field isolates (M114/2000, K170/2000 and K158/2001) were antigenically similar to IB virus strain 4/91 (Neutralization index 4.4 to 4.8 and VN titer > 11(log ) were recorded). Isolate (K110/2000) on the other hand, was antigenically similar to IB virus Mass. (M41) strain (HI titer >11 log was recorded). This 2 is the first time to identify IB virus strain antigenically similar to IB virus strain 4/91 in Sudan.}
    }